Replacement cardiac valves and methods of use and manufacture

ABSTRACT

Prosthetic mitral valves and their methods of manufacture and use.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to Provisional Application No.62/089,719, filed Dec. 9, 2014, which is incorporated by referenceherein.

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

BACKGROUND

The mitral valve lies between the left atrium and the left ventricle ofthe heart. Various diseases can affect the function of the mitral valve,including degenerative mitral valve disease and mitral valve prolapse.These diseases can cause mitral stenosis, in which the valve fails toopen fully and thereby obstructs blood flow, and/or mitralinsufficiency, in which the mitral valve is incompetent and blood flowspassively in the wrong direction.

Many patients with heart disease, such as problems with the mitralvalve, are intolerant of the trauma associated with open-heart surgery.Age or advanced illness may have impaired the patient's ability torecover from the injury of an open-heart procedure. Additionally, thehigh costs are associated with open-heart surgery and extra-corporealperfusion can make such procedures prohibitive.

Patients in need of cardiac valve repair or cardiac valve replacementcan be served by minimally invasive surgical techniques. In manyminimally invasive procedures, small devices are manipulated within thepatient's body under visualization from a live imaging source likeultrasound, fluoroscopy, or endoscopy. Minimally invasive cardiacprocedures are inherently less traumatic than open procedures and may beperformed without extra-corporeal perfusion, which carries a significantrisk of procedural complications.

Minimally invasive aortic valve replacement devices, such as theMedtronic Corevalve or the Edwards Sapien, deliver aortic valveprostheses through small tubes which may be positioned within the heartthrough the aorta via the femoral artery or through the apex of theheart. However, current cardiac valve prostheses are not designed tofunction effectively within the mitral valve. Further, current cardiacvalve prostheses delivered via a minimally invasive device are oftendifficult to place correctly within the native valve, difficult to matchin size to the native valve, and difficult to retrieve and replace ifinitially placed incorrectly. Furthermore, the mitral valve differs fromthe aortic valve in that the shape and anatomy immediately surroundingthe valve varies greatly from one side of the valve to the other. Oneaccess route for delivering replacement mitral valves requires atransseptal approach. Delivering a replacement valve transseptallyimparts limitations on the size of the delivery device and the deliveryprofile of the replacement valve within the delivery device, and impartscertain flexibility requirements for the replacement valve itself as itis delivered transseptally to the location of the native mitral valve.In some embodiments a sheath passing through a septum should be at mostabout 24F-28F.

Many current minimally invasive valve devices are made fromsuper-elastic Nickel-Titanium alloys. These super-elastic alloys allowhigh material strains, usually 6%-8%, without permanent deformation.Therefore, the alloys allow the valve devices to be packed into a small6-10 mm diameter tube for delivery while expanding to around 50 mmwithin the heart. Current manufacturing methods typically involvecutting the valve prosthesis, at least the expandable anchor portionthereof, from a single tubular element that has a uniform thicknessalong its length. In these cases, the cut expandable anchor may have thesame thickness along its length, and thus may not have varying stiffnessalong the length of the device. The inability to create an expandableanchor with varying thickness throughout can limit the functionality ofdifferent regions of the expandable anchor. Certain regions of theexpandable anchor may be limited in what they can be configured toperform by creating the valve from a single tubular element. This can beundesirable if there is a need to create certain functionality indifferent regions of the expandable anchor that result from the regionshave different thicknesses. Similarly, traditional expandable anchorsmade from a single tubular element do not have overlapping components(radially), wherein overlapping components may help impart additionalflexibility to portions of the expandable anchor, and/or allow theexpandable anchor to be collapsed to have a smaller delivery profile.Furthermore, in a single-piece construction, strains are limited to theelastic strain limit of the material, which may be too low for someapplications.

These and other deficiencies in existing approaches are describedherein.

SUMMARY OF THE DISCLOSURE

One aspect of the disclosure is a replacement mitral valve, comprising:a self-expandable anchor comprising a ventricular anchor, a centralportion, and an atrial anchor, the self-expandable anchor having aself-expanded configuration in which the ventricular anchor and theatrial anchor are flared radially outward relative to the centralportion such that the replacement mitral valve is configured to besecured within a mitral valve orifice, the ventricular anchor havinggreater stiffness in an axial direction than the atrial anchor when theexpandable anchor is in the self-expanded configuration; and a pluralityof replacement leaflets secured to the expandable anchor.

One aspect of the disclosure is a replacement mitral valve, comprising:a self-expandable anchor comprising a ventricular anchor integral with acentral portion, and an atrial anchor secured to the central portion butnot integral with the central portion, the self-expandable anchor havinga self-expanded configuration in which the ventricular anchor and theatrial anchor are flared radially outward relative to the centralportion such that the replacement mitral valve is configured to besecured within a mitral valve orifice; and a plurality of replacementleaflets secured to the expandable anchor.

One aspect of the disclosure is a method of manufacturing a replacementmitral valve, comprising creating a ventricular anchor integral with acentral portion; securing an atrial anchor to the central portion, theatrial portion not integral with the central portion or the ventricularanchor; and forming a self-expandable anchor that has a self-expandedconfiguration in which the ventricular anchor and the atrial anchor areflared radially outward relative to the central portion such that thereplacement mitral valve is configured to be secured within a mitralvalve orifice.

One aspect of the disclosure is a replacement mitral valve, comprising aself-expandable anchor comprising a ventricular anchor comprising aplurality of ventricular arches, a central portion, and an atrial anchorcomprising an annular frame with a plurality of atrial arches and aplurality of atrial apertures therethrough; the atrial anchor secured tothe central portion and not integral with the central portion, theself-expandable anchor having a self-expanded configuration in which theventricular anchor and the atrial anchor are flared radially outwardrelative to the central portion such that the replacement mitral valveis configured to be secured within a mitral valve orifice, wherein thecentral portion includes a plurality of central apertures therethrough,each of the plurality of atrial apertures in alignment with one of theplurality of central apertures to form a plurality of aligned apertures;a plurality of couplers, each of which extends through one of theplurality of aligned apertures and secures the central portion to theannular frame at the location of the aligned apertures; and a pluralityof replacement leaflets secured to the expandable anchor.

One aspect of the disclosure is a method of manufacturing a replacementmitral valve, comprising: providing a central portion of an expandableanchor, the central portion including a plurality of central aperturestherein that are disposed around a central opening; providing an atrialanchor that includes an annular frame comprising a plurality of atrialapertures therethrough; aligning each of the atrial apertures with acentral aperture to form aligned apertures; extending a coupler througheach of the aligned apertures from one side of the aligned apertures toa second side of the aligned apertures; plastically deforming each ofthe couplers to secure the central portion to the annular frame at thelocation of the couplers; and forming a self-expandable anchor that hasa self-expanded configuration in which the ventricular anchor and theatrial anchor are flared radially outward relative to the centralportion such that the replacement mitral valve is configured to besecured within a mitral valve orifice.

One aspect of the disclosure is a replacement mitral valve, comprising:a self-expandable anchor comprising a ventricular anchor, a centralportion comprising a plurality of apertures therethrough that aredisposed around the central portion, and an atrial anchor, theself-expandable anchor having a self-expanded configuration in which theventricular anchor and the atrial anchor are flared radially outwardrelative to the central portion such that the replacement mitral valveis configured to be secured within a mitral valve orifice; an annularstrut frame comprising a plurality of apertures therethrough around thestrut frame, the strut frame disposed radially within the centralportion, each of the plurality of annular strut frame apertures alignedwith one of the plurality of central portion apertures, the annularstrut frame secured to the central portion at the location of theplurality of strut frame apertures; and a plurality of replacementleaflets secured to the annular strut frame.

One aspect of the disclosure is a method of manufacturing a replacementmitral valve, comprising creating a ventricular anchor, a centralportion, and an atrial anchor, the central portion including a pluralityof apertures disposed around a central opening defined by the centralportion; providing an annular strut frame, the strut frame comprising aplurality of apertures therethrough around the strut frame, positioningthe annular strut frame radially within the central portion; aligningeach of the plurality of strut frame apertures with an aperture on thecentral portion to create a plurality of overlapped apertures; providinga plurality of couplers, and extending a coupler through each of theplurality of overlapped apertures; plastically deforming the pluralityof couplers to secure the central portion to the annular strut frame atthe locations of the plurality of couplers; and forming aself-expandable anchor that has a self-expanded configuration in whichthe ventricular anchor portion and the atrial anchor portion are flaredradially outward relative to the central portion such that thereplacement mitral valve is configured to be secured within a mitralvalve orifice.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a portion of an exemplary valve prosthesis in an expandedconfiguration.

FIG. 2 is a side view illustrating an exemplary prosthesis includingleaflets.

FIG. 3 illustrates an integral central portion and ventricular anchorafter being cut from a sheet of material.

FIG. 4 is a perspective view illustrating an integral central portionand ventricular anchor after being rolled with ends secured.

FIGS. 5A and 5B show formation of an expanded configuration of anintegral central portion and ventricular anchor using a heat shapingfixture.

FIGS. 6A and 6B show an integral central portion and ventricular anchorafter being shape set in an expanded configuration.

FIGS. 7A and 7B illustrate atrial frames of an atrial anchor.

FIG. 8 illustrates an atrial frame of an atrial anchor secured to acentral portion.

FIG. 9 illustrates an expanded anchor after a second atrial frame of anatrial anchor has been secured to the central portion.

FIG. 10 shows formation of an expandable anchor after the atrial anchorhas been secured thereto, using a heat shaping fixture.

FIGS. 11A and 11B illustrate an expandable anchor in an expandedconfiguration before struts have been secured thereto.

FIGS. 12 and 13 illustrate exemplary couplers.

FIG. 14 illustrates an exemplary strut.

FIG. 15 illustrates an exemplary expandable anchor with three strutssecured thereto.

FIG. 16 illustrates an exemplary prosthesis including leaflets.

FIG. 17 illustrates a prosthesis including leaflets and an atrial skirt.

FIG. 18 illustrates an exemplary sliding valve strut.

FIG. 19 illustrates an exemplary strut frame, including a plurality ofstruts.

FIG. 20 illustrates an exemplary strut frame, including a plurality ofstruts.

FIG. 21 represents a collapsed expandable anchor, collapsed fordelivery.

DETAILED DESCRIPTION

This disclosure includes replacement heart valves (also referred hereinas prosthetic heart valves), methods of manufacturing replacement heartvalves, including subassemblies thereof, and methods of usingreplacement heart valves. This disclosure describes the prostheses inthe context of replacement mitral valves, but it is conceivable that theprostheses herein can be used or modified to be used as otherreplacement heart valves. In some embodiments the replacement heartvalves are self-orienting (at least on one side) replacement mitralvalves configured to be delivered using minimally invasive techniques.

The replacement heart valves herein include an expandable anchor thatincludes an atrial anchor (e.g., configured to be placed on an atrialside of a mitral valve annulus), a ventricular anchor (e.g., configuredto be placed on a ventricular side of a mitral valve annulus), and acentral portion axially between the atrial and ventricular anchors. Theexpandable anchor is adapted to be collapsed towards a collapseddelivery configuration, and is adapted to expand towards an expandableconfiguration. The replacement heart valves also include a plurality ofstruts secured to at least one of the central portion, the ventricularanchor, or the atrial anchor, the struts being secured to a plurality ofreplacement leaflets. The struts can be considered part of theexpandable anchor, and in embodiments herein are configured to deform asthe rest of the expandable anchor is collapsed. It may be possible toincorporate struts that are not deformable, but which are still securedto the expandable anchor. These types of struts may not be consideredpart of the expandable anchor but are secured to the expandable anchor.The struts extend distally, that is, towards the ventricular anchor. Inthe context of replacement mitral valves, the “distal” end of thereplacement valve refers to the end of the replacement valve that is tobe positioned on the ventricular side of the annulus, while “proximal”end refers to the end of the replacement valve that is to be positionedon the atrial side of the annulus. “Distally” in the context of deliverycan be used to refer to a location closer to the left ventricle than theleft atrium, while “proximally” is generally used to refer to a locationcloser to the left atrium than the left ventricle.

In some embodiment the expandable anchor is adapted to completelyself-expand, and in some embodiments it is configured to be partiallyself-expanding and partially expand by non-self-expanding influences(e.g., a balloon). The expandable anchors can be made of (or partly madeof) a super elastic material such as nitinol.

One of the advantages of some of the replacement heart valves herein,and the methods of manufacturing provided herein, is that differentregions of expandable anchors can have different physicalcharacteristics that would not have been possible with alternativedesigns. For example, in some embodiments the expandable anchor ismanufactured from two or more separate components of material that aresecured together during manufacturing. By securing two or more differentcomponents together to create the expandable anchor, different startingmaterials can be used for the different components, and thus differentmaterials with different properties can be used for different regions ofthe expandable anchor. The different properties can be chosen to impartdesired physical characteristics to different regions of the expandableanchor.

When two components are secured together during manufacturing they areconsidered to be non-integral, or non-monolithic, components. Differentportions of the expandable anchor that are made from the same startingmaterial are considered to be integral, or monolithic. For example, amanufacturing step could include cutting a strut and an expandableanchor from different pieces of starting material, and securing themtogether, and they would be considered non-integral. In someembodiments, when one or more components are secured together, thecoupling of the two components can be made so that the two componentsare rigidly secured at the coupling, or so that the two components canmove to some degree at the location of the coupling of the twocomponents (e.g., pivotable).

In methods of use, the prostheses described herein can be delivered to acardiac valve orifice, such as the mitral valve, by using minimallyinvasive techniques to access the cardiac valve. Access routes andprocedures are known, such as making small incisions in the patient'sbody and passing the prosthesis through the apex of the heart to, forexample, a mitral valve. An additional exemplary access route includesdelivering the valve through the venous system and into the left atriumvia a transseptal puncture. A transseptal approach can impart sizelimitations on the delivery and thus the delivery profile of thereplacement heart valve. Additionally, a transseptal approach can alsoimpart certain flexibility requirements on the replacement heart valve.The replacement heart valves herein are configured to be collapsed intoa delivery configuration so they can fit within a delivery device. Thereplacement heart valves can be delivered to the treatment site withinthe delivery device and then deployed from the delivery device. Ifnecessary, the replacement valves can be repositioned, re-sheathed(partially or completely) if necessary, and then re-deployed.

When the replacement heart valve has been delivered near the mitralvalve, the ventricular anchor can be deployed first in a cardiacchamber, such as the ventricle, and retracted to a seated positionagainst the valve orifice, such as the mitral valve orifice. Then thecenter portion and atrial anchor portion may be deployed in anothercardiac chamber, such as the atrium, wherein the expansion andreconfiguration of the atrial anchor and the central portion sandwichesthe valve orifice securely between the anchors that have been deployedon either side of the annulus. Other exemplary aspects of the methods ofdelivery described in U.S. Pat. No. 8,870,948, issued Oct. 28, 2014 canbe incorporated into any of the methods of delivery herein.

Replacement heart valves herein are configured to be secured in thenative valve orifice by sandwiching the cardiac orifice betweenventricular and atrial anchors, which are larger in diameter than thevalve orifice, and by applying a radial force from the center portionoutward against the cardiac orifice. Additional engagement between theprostheses and cardiac tissue can be added with wire hooks extendingfrom the valve prostheses.

FIG. 1 is a perspective view of a portion of an exemplary mitral valveprosthesis in an expanded configuration after an expandable anchor andstruts have been secured together. The portion of the replacement valveshown in FIG. 1 may be referred to as an anchor subassembly, whichexcludes leaflets and any skirts that may be incorporated into the finalreplacement valve. FIG. 1 shows a view from an atrial side to aventricular side. Expandable anchor 1 includes an atrial anchor 2, aventricular anchor 4, and a central portion 3 therebetween. In thisembodiment atrial anchor 2 is configured and adapted to be disposed onan atrial side of a mitral valve orifice, and ventricular anchor 4 isconfigured and adapted to be disposed on a ventricle side of the mitralvalve orifice. In some uses, however, anchor 1 may be implanted so thatatrial anchor 2 as shown is positioned on the ventricle side andventricular anchor 4 is positioned on the atrial side. Three struts 5are secured to the expandable anchor, and in this embodiment are securedto central portion 3, and at least a portion of struts 5 are disposedradially inward relative to central portion 3. Struts 5 are extending,or pointing, towards ventricular anchor 4 and away from atrial anchor 2.

Radially inner surfaces of the expandable anchor and the struts definecentral opening 6, which is radially within the expandable anchor. Theradially inner surfaces of central portion 3 substantially define theperimeter of central opening 6. Replacement leaflets, which are notshown in FIG. 1 for clarity, are secured to struts 5 and are disposed atleast partially in central opening 6, and are configured to controlblood flow therethrough.

In the expanded configuration shown in FIG. 1 (which is also an“as-manufactured” configuration), atrial anchor 2 and ventricular anchor4 extend radially outward from central portion 3, and are considered toflare outward relative to central portion 4. Atrial anchor 2 andventricular anchor 4 can also be considered flanged relative to centralportion 3. The flared configuration of atrial and ventricular anchors 2and 4 relative to central portion 3 is described in the context of aside view of the expandable anchor, as can be seen in FIG. 2 (whichillustrates leaflets secured to struts). In some embodiments one or moreof the flared anchors are orthogonal to a longitudinal axis “LA”(illustrated in FIG. 2) passing through central opening 6. In someembodiments the flared anchor portions have a smooth curve radiallyoutward. In some flared configuration the two anchors and the centralportion define a general “C” or “U” shape in a side view of theexpandable anchor. A “C” or “U” configuration is not limited tosymmetrical configurations, however, as there can be slight deviationfrom a true “U” and still be considered to be U-shaped. For example, theexpandable anchor could define a “C” configuration, but one of theatrial and ventricular anchors could have a tighter curvature than theother anchor. When the anchor portions are flared and create a “C”shaped configuration, the atrial and ventricular anchors are slightlycurved inward towards the central portion at their respective ends. Insome embodiments atrial anchor 2 and ventricular anchor 4 aresubstantially parallel to one another, such as exactly parallel to oneanother. In some embodiments the configuration of the flared anchorscreates a substantially constant radius of curvature (i.e., asemi-circle) so that stress across anchors 2 and 4, and central portion4 is balanced, thereby reducing fatigue or wear at any one point alongthe prosthesis.

In some embodiments the expanded anchor 1 (not including the struts) hasa length “L” (see FIG. 2, measured from the atrial end to theventricular end, parallel to the longitudinal axis LA) of 6-12 mm, suchas 6-11 mm, 6-10 mm, 6-9 mm, 7-11 mm, 8-10 mm, 6 mm, 7 mm, 8 mm, 9 mm,10 mm, 11 mm, and 12 mm. In some embodiments the length of the expandedprosthesis, including the struts (“LS” as shown in FIG. 2), has a lengthof 16-20 mm, such as 17-19 mm, 16 mm, 17 mm, 18 mm, 19 mm, and 20 mmwith the struts. In some embodiments, the expanded anchor has anexpanded diameter (“D” in FIG. 2) of about 35 mm to about 75 mm, such asabout 45 mm to about 65 mm. In some of those embodiments the device isconfigured to be collapsed to a collapsed configuration in which it hasa collapsed diameter D of 7 mm to 12 mm (i.e., the prosthesis can becollapsed down to fit within a 21-36 French catheter). In someembodiments the central opening 6 diameter (“DC” in FIG. 10A) is between20 mm and 45 mm, such as between 25 mm and 40 mm, such as between 28 mmand 38 mm. In embodiments in which central opening 6 is not a perfectcircle, the central opening diameter refers to the greatest lineardimension between points on the central portion, when viewed in an endview such as FIG. 10A.

Additionally features of exemplary expandable anchor 1 will now bedescribed in the context of an exemplary method of manufacturing theexpandable anchor 1. Other manufacturing processes, whole or partial,can be used as well. FIGS. 3-6B illustrate an exemplary method ofmanufacturing a ventricular anchor 4 and central portion 3 that areintegral, or monolithic. FIG. 3 illustrates integral central portion 4and ventricular anchor 3 of expandable anchor 1 that have been cut(e.g., laser cut) out of a flat sheet of material. In some embodimentsthe material is a nitinol sheet, and in some exemplary embodiments thenitinol sheet is 0.3 mm to 0.35 mm thick. In these embodiments theventricular anchor and central portion are thus 0.3 mm to 0.35 mm thick.

In this embodiment central portion 3, when cut, comprises a plurality ofdiamond-shaped cells 7 (only one labeled for clarity), as shown in thedotted lines in FIG. 3. In this embodiment there are twelve cells 7 incentral portion 3, all of which have a general diamond shape when laidflat, as in the view shown in FIG. 3. Central portion 3 can have feweror more cells, the cells can have configurations other than generaldiamond shapes, and the cells need not all have the same configuration.In this embodiment each central portion cell 7 has an aperture 26 at oneof the bends in the diamond shape near the atrial end of central portion3, but in other embodiments not every cell 7 has an aperture 26. Forexample, every other cell could have an aperture 26. In this embodimentapertures 26 are aligned axially (i.e., as shown they are in a “row”),but in other embodiments there are not. For example, if the cells havedifferent configuration some apertures 26 may not be aligned, or in thesame “row” with other apertures. Central portion 3 also includes aplurality of apertures 36 formed in material where adjacent cells 7meet, as shown in FIG. 3. In this embodiment apertures 36 are axiallyaligned, but in other embodiments they need not be aligned. In thisembodiment apertures 36 are in the middle of cells 7 measured in anatrial-to-ventricular end direction (up and down in FIG. 3).

Expandable anchor 1 also includes ventricular anchor 4. In thisembodiment ventricular anchor 4 includes a plurality of arches 42 thatextend from the central portion towards the ventricular end. Theconfigurations of arches 42 are generally triangular-shaped, “pointing”towards the ventricular end, and include two sections of material and abend in between the two sections of material. As shown, in each arch 42,the material first extends away from central portion 4, forms a bend atthe ventricular end of the anchor, and then extends back towards centralportion 4. Arches 42 are triangular shaped in this embodiment, and theventricular ends can be described as tips of the arches, and in thisembodiment are rounded. A plurality of spaces 49 (only two are labeledfor clarity) between adjacent arches 42, the configurations and sizes ofwhich are defined by the configuration of adjacent arches 42, areconfigured to advantageously allow the sub-valvular structures, such aschords, to slide between adjacent arches 42 when the ventricular anchoris expanded on the ventricular side of the mitral valve annulus. Theconfiguration of arches 42, and thus the plurality of spaces 49, canalso provide easier collapse of the ventricular anchor 3 radiallyinwards when the anchor is collapsed (e.g., for delivery). The arch 42tips at the ventricular end are rounded, or curved (as opposed to abruptor sharp) to avoid damaging the tissue when implanted. Additionally, thetip of each arch 42 includes optional hooks 44 extending from the tip.The hooks 44 can face in towards the central opening 15 and embed intothe annulus tissue, thereby helping to resist the pressure build-up onthe ventricular side of the aorta.

In some embodiments any of apertures 26, 36, and 46 can be circular. Insome embodiments any of the apertures (such as all of them) can bebetween 0.3 mm and 0.8 mm in diameter, such as 0.4 mm-0.7 mm, 0.5 mm-0.6mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, and 0.8 mm in diameter.

In the embodiment in FIG. 3 the same starting material is used to makethe central portion 3 and ventricular anchor 4. In this embodimentventricular anchor 4 and central portion 4 are cut from a flat sheet ofmaterial (e.g., nitinol). In other embodiments the integral centralportion 3 and ventricular anchor 4 can be cut from a tubular startingmaterial. After ventricular anchor 4 and central portion 3 are cut asshown in FIG. 2, a next step in manufacturing the expandable anchor isthat it is then rolled into a generally cylindrical configuration andthe ends of the material are secured together, as shown in the generallycylindrical configuration in the perspective view of FIG. 4. In thisembodiment apertures 36 a and 36 b, and 46 a and 46 b, (FIG. 3) aresecured together once the apparatus is reconfigured into the cylindricalconfiguration in FIG. 4. An exemplary method of securing the ends is byriveting the ends at the apertures, wherein a rivet is placed withinaligned apertures 36 a and 36 b, and then the free rivet end is deformedto secure the ends of the apparatus and maintain the cylindricalconfiguration shown in FIG. 4.

Alternatively, in some embodiments, integral central portion 3 andventricular anchor 4 can be cut from a tubular element to form theconfiguration in FIG. 4. In these embodiments ends of the device neednot be coupled together since the apparatus has the configuration inFIG. 3 when cut from the tubular element.

Once the apparatus is in the cylindrical configuration shown in FIG. 4(whether cut from a flat sheet and rolled, or cut from a tubularelement, or from another process), an exemplary subsequent step is toreshape the partial anchor into a shape memory configuration. FIGS.5A-6B illustrate an exemplary shaping process and resulting reconfiguredapparatus. As shown in FIGS. 5A and 5B, the generally cylindrical shapeddevice is placed in a heat shaping fixture 99. Once in the heat shapingfixture, the column can be heated, such as in a salt bath at 915 degreesfor 3 minutes, and then quenched in water in order to set the shape ofthe ventricular anchor and central portion. The shape memoryconfiguration of the integral central portion 3 and ventricular anchor 4are shown in the perspective views in FIGS. 6A and 6B. FIG. 6A shows aperspective view looking from the central portion to the ventricularanchor, and FIG. 6B shows a view looking from the ventricular anchor tothe central portion. The reference numbers in FIGS. 6A and 6B aredescribed herein. A side view of the configuration of the anchor fromFIGS. 6A and 6B can also be seen in the replacement valve in FIG. 2, butthe atrial anchor and leaflets have not been added yet to the partialdevice shown in FIGS. 6A and 6B.

In this exemplary embodiment, once the integral ventricular anchor 4 andcentral portion 3 are shape set (as shown in FIGS. 6A and 6B), atrialanchor 2 is secured to central portion 3. In this embodiment atrialanchor 2 comprises first frame 122 and second frame 222, which are shownin FIGS. 7A and 7B, respectively. In this embodiment frame 122 and 222have the same configuration and are interchangeable. In this embodimentsecond frame 222 is an inner frame, and first frame 122 is an outerframe in that first frame 122 is disposed radially outward relative toinner frame 222. Inner frame 222 also sits proximal to outer frame 122,although in this embodiment the two atrial frames have the sameconfiguration and thus their designation of inner and outer can beswitched.

As shown in FIGS. 7A and 7B, atrial frame 122 includes a plurality ofarches 111 a-111 f (also referred to herein as arcs, arcuate portions,curved portions, or petals), and atrial frame 222 includes a pluralityof arches 211. In this embodiment each arch 111 includes a peak 113, andadjacent arches meet at valleys 115 (only one peak and two valleyslabeled for clarity). A peak is generally considered the location wherethe radial distance from the valley is greatest. In this embodimentthere are six peaks and six valleys in each of frames 122 and 222. Inthis embodiment each frame includes apertures disposed at each of theframe valleys. Frame 122 includes six apertures 116 (one labeled), inthis embodiment one at each valley 115. Frame 222 includes six apertures226, one at each valley. In other embodiments a frame may include moreor fewer arches, such as between two and fifteen arches.

Atrial frame 222 includes arches 211 a-211 f, each comprising a peak,and valleys one either side of a peak. The arches 211 meet at thevalleys, each of which has an aperture 226 therethrough. In thisembodiment all of the arches, on both of frames 122 and 222, comprise aprotuberance or extension 118 (only one protuberance labeled, which ison frame 122 in FIG. 7A) near the center, or midline, of each arch. Themidline is the middle of the length of the arch, as measured linearlybetween valleys on either side of the arch. The protuberance is aportion of the arch that has increased curvature relative to adjacentportions of the arch. During collapse of the prosthesis, theprotuberances 118 can be pulled upon, providing easier collapse andreducing strain in the arches when the anchor is collapsed (e.g., fordelivery).

In some embodiments either or both of atrial frames 122 and 222 are cutout of a flat sheet, such as a sheet of nitinol, as in the case in FIGS.7A and 7B. In some embodiments the sheet of nitinol is 0.2 to 0.25 mmthick, which results in frames that are 0.2 mm to 0.25 mm thick. In thisembodiment all of the arches on each frame are integral, or made fromthe same starting material. Frames 122 and 222 have an annularconfiguration, as can be seen in FIGS. 7A and 7B, even though they arenot perfectly annular. Annular in this context refers to structures(e.g., atrial frames) that, once assembled as part of the expandableanchor, subtend 360 degrees around a longitudinal axis LA of theexpandable frame. In other words, they are generally annular even thoughthey are not perfectly annular. A longitudinal axis as used herein doesnot impart symmetry to the replacement heart valve, but generally refersto an axis that passes through a central portion of the central openingin the expandable anchor.

In the manufacturing of the expandable anchor, atrial frames 122 and222, once formed (e.g., cut), are secured to central portion 3. In thisembodiment there are twelve apertures 26 at one end of central portion3, as can be seen clearly in FIG. 3. Each of frames 122 and 222 has sixapertures 116 and 226, respectively, and in this embodiment each onedisposed in a valley of the frame between arches. To secure atrial frame222 to central portion 3, each aperture 226 is aligned with an aperture26 in central portion, the relative positions of which can be seen inFIG. 8. FIG. 8 shows frame 222 assembled to central portion 3 at aplurality of aligned apertures. In this embodiment frame 222 and centralportion 3 are configured, including the location of the apertures, suchthat apertures 226 on frame 222 are aligned with alternating apertures26 in central portion 3, as shown in FIG. 8. In this embodiment frame222 and central portion 3 are secured together at the location of thealigned apertures by riveting the components together at the locationsof the apertures. A rivet is placed through two aligned apertures, andthen one side of the rivet is plastically deformed to secure the atrialframe to the central portion at the location of the aligned apertures.

After frame 222 is secured to central portion 3 (which can be seen inFIG. 8), frame 122 is secured to central portion 3 in the same manner,except in this embodiment the six apertures 116 in frame 122 are firstaligned with the six apertures 26 that are not yet riveted to frame 222(the six “open” apertures 26 can be seen in FIG. 8). FIG. 9 shows theexpandable anchor after frame 122 is secured to central portion 3, whichin this embodiment is also done with rivets like frame 222. Frames 122and 222 are rotationally offset with one another with respect to centralportion (which can be seen in FIG. 9), and in this embodiment the peaksof one frame are rotationally aligned with a valley of the other frame.Frames 122 and 222 overlap at frame sections between the valleys andpeaks, and are in contact with one another where they overlap (but inother embodiments the memory configuration may be such that frame areslightly apart such that they do not contact one another where theyoverlap), which can be seen in FIG. 9. In this embodiment the framesoverlap between the peaks and valleys. In this configuration arches 111and 211 of the two frames are considered to be out of phase relative toone another, as can be seen in FIG. 9. For example, arches 111 can beapproximately 30 degrees out of phase relative to arches 211. That is,arches 111 of the first frame 122 can overlap with arches 211 of thesecond frame 222 such that, for example, a single arch 111 of the firstouter frame 122 overlaps with half of two underlying arches 211 of thesecond outer frame 222. In some embodiments, only some arches are out ofphase with one another while other arches are in-phase with one another.When frames 122 and 222 are secured to central portion 3, thecombination of overlapping frames 122 and 222 can form a substantiallycircular, or annular, outer perimeter (in an end view of the device suchas in FIG. 9), which can provide a smooth surface to sit against theatrial tissue.

Frames 122 and 222 are secured to central portion 3, but they are notdirectly attached to one another. This configuration allows for relativemovement between frames 122 and 222. The relative movement around atrialanchor 2 may allow for atrial anchor 2 to conform better to the tissueon the atrial side of the annulus (there may be patient to patientvariability) and help seal the expandable anchor in place better on theatrial side. For example, an arch 111 can be movable relative to the twoarches 211 that it overlaps. That is, the outer perimeter of an arch 111can flex in the direction of the longitudinal axis (axially) and/ortranslate relative to the two arches 211 that it overlaps, while theradially inner portions of the frames are secured to the central portionof the expandable anchor. The outer perimeter of the atrial anchoressentially creates a substantially circular, or annular, flexible sealwhose arches can flex as needed relative to overlapping arches to betterconform to the patient's anatomy and help create a better seal againstatrial tissue.

After atrial anchor 2 is attached to central portion 3 (shown in FIG.9), the expandable anchor can be heat shaped again. FIG. 10 shows theexpandable anchor (ventricular anchor 4 arches 42 can be seen in FIG.10) after it is placed into a shaping fixture 303 and heated, such as at915 degrees for 3 minutes, and then quenched in water to form theexpandable anchor. The configuration of the expandable anchor after thisshape setting step is shown in FIGS. 11A and 11B, with reference numbersdescribed above.

The exemplary expandable anchor shown in FIGS. 11A and 11B, which isshown in an expanded memory configuration, has a ventricular anchor andan atrial anchor that are flared radially outward relative to thecentral portion such that the self-expandable anchor is configured tosecure the replacement mitral valve to a mitral valve orifice in theself-expanded configuration. In this embodiment ventricular anchor 4,which includes plurality of arches 42, has a greater stiffness in theaxial direction than the atrial anchor when the expandable anchor is inthe expanded configuration. FIG. 2 illustrates hypothetical axiallyforces “F” applied to the ventricular and atrial anchors, upon whichventricular anchor 4 has a greater resistance to deformation than atrialanchor 2. The stiffness comparison is generally considered in responseto a hypothetical applied force on the radially outer portions of theventricular and atrial anchors, as shown by forces F in FIG. 2.

One aspect of the embodiment in FIGS. 1-11B that contributes to theventricular anchor being stiffer than the atrial anchor in an axiallydirection is that, in this embodiment, the arches in the ventricularanchor have a thickness that is greater than the thickness of each ofatrial frames 122 and 222, and thus the thickness of the arches in thetwo atrial frames. In this embodiment, however, the thickness of theatrial anchor at the location where the frames overlap is thicker thanthe thickness of the ventricular arches due to the double layer ofmaterial at the overlapping locations. In some merely exemplaryembodiments the ventricular arches are 0.3 mm to 0.35 mm thick, whichcan be provided by cutting the ventricular anchor portion from a sheetof material that is 0.3 mm to 0.35 mm thick. In some embodiments theatrial anchor frames, and thus the arches, are 0.2 mm to 0.25 mm thick.

An additional aspect of the embodiment in FIGS. 1-11B that contributesto the ventricular anchor being stiffer than the atrial anchor is thatthe ventricular anchor is formed integrally with the central portion,whereas the atrial anchor portion is made from different startingmaterial and then attached to the central portion. While this embodimentincludes two different frames in the atrial anchor portion, in someembodiments the atrial anchor includes only one of the frames. Forexample, in some alternate embodiments, there is only one atrial frame,which comprises a plurality of peaks and valleys. In these alternativeembodiments, while there are not any overlapping arches and thus norelative movement between overlapping arches, the ventricular anchor isstill stiffer than the atrial anchor, in part due to the points ofattachment between the central portion and the atrial anchor, andbecause the ventricular anchor has thicker arches than the arches of theatrial anchor.

In some alternative embodiments the ventricular anchor arches have thesame thickness as the atrial arches, but the integral formation of theventricular arches with the central portion can provide for theincreased stiffness relative to the atrial arches. Additionally, even indesigns where there is only one atrial anchor frame, the ventriculararches can have the same thickness as the atrial arches, and the greaterstiffness of the ventricular arches is due at least partially to theintegral formation of the ventricular anchor and the central portion.

In alternative embodiments, the ventricular anchor, central portion, andatrial anchor (regardless of the number of atrial frames) are allintegral, but the ventricular arches are thicker than the atrial arches.In one exemplary method of manufacturing, the entire anchor could beintegral and cut from a tube, but the central and atrial portions couldbe ground down to have a smaller thickness than the ventricular portion.Thus even though the three portions of the expandable anchor are allintegral, the ventricular side is still stiffer in the axial directiondue at least partially due to the thicker ventricular arches.

In some embodiments the ventricular portion, central portion, and atrialportion all have different thicknesses. For example, each of the threeportions could be made from different starting materials (i.e.,non-integral) with different thicknesses, and then secured together.Alternatively, the three portions could be integral and cut from a tube,and then one or more portion could be ground down to achieve a desiredthickness in each portion, wherein the end result is that the threesections can have any desired thickness, such as three differentthicknesses.

Some of the increased flexibility (less stiff) of the atrial arches isalso due to the length of the atrial arches (the linear distance betweenvalleys of the atrial arches) compared to the lengths of the ventriculararches (the linear distances between valleys of the ventricular arches).Ventricular valley linear distance “VV” is shown in FIG. 3, and atrialvalley linear distance “AV” can be seen in FIG. 7A. In the embodimentsshown herein the ventricular valley distance is less than the atrialvalley distance (for both of the atrial frames in this embodiment).

In some embodiments the height of the ventricular arches “VH” (shown inFIG. 3), before the outward flare is imparted to the arches, is greaterthan VV. In some embodiments the two distances are substantially thesame.

The embodiment in FIGS. 1-11B is also an example of a self-expandableanchor comprising a ventricular anchor integral with a central portion,and an atrial anchor secured to the central portion but not integralwith the central portion. In this embodiment the expandable anchor(excluding the struts), when in an expanded configuration (which can beself-expandable) has a length L, which can be seen in FIG. 2. Midline,or half the length, is indicated as “M” in FIG. 2. In this embodimentthe atrial anchor is disposed solely on the atrial side of the midline.That is, the atrial anchor portion is secured to the central portion onan atrial side of the expandable anchor. In this embodiment centralportion 3 defines the radially innermost portion of the expandableanchor (excluding the struts and related structure).

In alternative embodiments the ventricular anchor can similarly benon-integral with the central portion and then secured thereto. Forexample, the ventricular anchor can comprise a ventricular annular frame(similar to an annular atrial frame) that is secured to the centralportion, such as with rivets as described with respect to some atrialannular frames herein.

In embodiments in which the atrial anchor is not integral with the restof the anchor, and it secured to the rest of the anchor duringmanufacturing, the coupling between the atrial anchor and the rest ofthe expandable anchor can be movable or non-movable couplings. In somesituations it may be desirable to have some degree of movement betweenthe atrial anchor and the central portion at the location of thecoupling(s). In some scenarios it may be desirable to limit as muchmotion as possible at the location of the couplings. For example, whenrivets are used to secure the atrial anchor to the central portion,examples of which are provided herein, the riveting process can betailored to accommodate the desired degree of movement between theriveted components. Too much movement between components due to thecoupling could, however, lead to material fatigue and failure. Movablecoupling as used herein can be thought of as hinge points between twocomponents, or hinge locations. The hinge allows for some movementbetween the two components, which can enhance, for example, the atrialanchor conforming to atrial tissue. In addition, an expandable anchorthat is constructed from more than one component coupled at rivets orhinges may flex freely at the couplings and reduce ultimate materialstrains.

Any of the central portion, the ventricular and atrial anchor portions,and the struts can be formed from different starting materials from oneanother (i.e., non-integral). Non-integral components can, if desired,allow the various components to be of different flexibilities andstiffnesses, and it can also provide for radial overlapping (relative tothe longitudinal axis of central opening) of the components. Forexample, described above, the atrial anchor can be configured to be moreflexible (less stiff) than the ventricular anchor to provide betterconformability and sealing in the atrium, while the stiffer ventricularanchor can provide sufficient resistance to pressure in the ventricle.In some embodiments, a thicker material can be used to form the centralportion and the ventricular anchor while a thinner material can be usedto form the atrial anchor. For example, the ventricular anchor can havea thickness of 0.25 mm to 0.35 mm while the atrial anchor can have athickness of 0.15 mm to 0.25 mm. Further, in some embodiments, thelength of the arches of the ventricular anchor (also referred to hereinas the linear distance between valleys) can be shorter than the lengthsof the arches of the atrial anchor to increase the stiffness of theventricular anchor relative to the proximal anchor. For example, in someembodiments the arches of the atrial anchor are between 25 mm and 35 mm,such as approximately 30 mm long, while the length of the arches of theventricular anchor are between 15 and 25 mm long, such as approximately20 mm long.

Rivets as used herein are an example of a coupler, as that term orderivatives thereof is used herein. The locations where components aresecured to one another may be referred to as a coupling herein. Couplingalso refers to the two components that are secured together. Riveting asused herein is an example of a method that plastically deforms a couplerto secure two or more components together at a coupling.

FIGS. 12 and 13 show exemplary rivets that can be used to secure two ormore components together herein (including the struts described below).Rivet 130 a as shown in FIG. 12 is a stepped rivet and rivet 130 b asshown in FIG. 13 is a straight rivet. The rivets can be inserted throughthe apertures described herein and the second ends 135 and 137,respectively, can then be plastically deformed using known rivetingtechniques to secure the two or more components together. The rivets canbe made of a suitable implantable material, such as platinum,platinum-iridium alloy, tantalum, nickel-titanium alloy, or titanium andtitanium alloys, such as titanium 6-4eli. In some embodiments, theriveted coupling can be such that one or more rivets are not tightenedall the way down to the secured components, which allows for hinging ofthe coupling, if desired. Rivets used for hinging may be made ofmaterials suitable for implantable bearing surfaces such as Nitronic 60alloy, or nitinol. Hinge pins can be coated with low-friction,high-durability coatings, such as diamond-like coating, or titaniumnitride. Referring to FIG. 13, a stepped rivet can be used as a hingepin. The stepped rivet can include a step, or change of diameter section131, such that one attached component can ride along a portion of thestep. In some embodiments, hinge pins can be used to attach the atrialanchor, thereby providing more flexibility for the atrial anchor.Riveting and hinging can advantageously provide for better collapsingfor delivery, including a smaller delivery profile, the advantages ofwhich are described herein, such as for transseptal access to the mitralvalve. Exemplary dimensions of rivets are shown in FIGS. 12 and 13, inmillimeters.

Use of rivets and hinges (as opposed to, for example, crimp tubes) canprovide an additional benefit of preventing cracking that can occur assingle pieces of material flex and move. Additionally, rivets and hingescan provide various degrees of relevant movement between portions of thevalve, which can allow the valve to be collapsed into a smaller deliveryprofile for delivery. The relative movement can also provide increasedflexibility of the valve during delivery. Rivets can also allow for avariation in the relative orientation of the riveted components. In someembodiments, rivets provide increased flexibility that allows forgreater trackability during delivery and better self-centering of theanchor against cardiac tissue (i.e., provides advantages for both accessand conformability to the anatomy).

The couplings herein (e.g., riveting) also allow different section ofmaterial with different physical properties to be secured to oneanother. This allows different sections of the expandable anchor to havedifferent properties (e.g., stiffness) than other sections, as may beneeded based on, for example, anatomical requirements. For example,atrial anchors can be made thinner than the central portion and/orventricular anchors.

The prostheses herein also include a plurality of struts, to which areattached replacement leaflets, which are configured to control bloodflow therethrough. FIGS. 1 and 15 are perspective views illustratingthree struts 5 that are individually secured to central portion 3 of theexpandable anchor, and are extending distally (towards the ventricularanchor). FIG. 1 is a view from the atrial side to the ventricular side,while FIG. 12 is a view from the ventricular side to the atrial side.FIG. 14 illustrates one of the three struts 5 in the embodiment in FIGS.1 and 12. In this exemplary embodiment three individual struts 5 aresecured to central portion 3 at riveted couplings, in the same generalmanner as how the atrial anchor can be secured to the central portion,as described herein. Struts 5 have a ventricular end 59 and an atrialend 61, as shown in FIG. 14. Atrial end 61 includes a plurality ofapertures 57 a, 57 b, and 57 c, which are configured to be secured toapertures 36 in the central portion, such as using rivets or hinge pinsas described herein. Struts 5 includes three elongate portions 55 a, 55b, and 55 c, each extending from ventricular end 59 and each of whichhas a free end at the atrial end 61. The free ends include the apertures57 a-c. Elongate portion 55 b has a straight configuration, whileelongate portions 55 a and 55 c are curved and flared outward relativeto elongate portion 55 b. Struts 5 have a generally triangularconfiguration, pointing in the distal direction. The triangular struts 5can provide vertical strength and lateral flexibility. Elongate portions55 a and 55 c are curved and have a longer overall length than themiddle straight elongate portion 55 b so as to provide an arched shapethat lowers stress along the leaflets. Further, the atrial ends 61 ofeach outer elongate portion 55 a and 55 c can include a spring 51 a and51 c, respectively, such as a clock spring, that is configured tocompensate for the difference in lengths of elongate portions 55 a, 55b, and 55 c when the prosthesis 1 is collapsed inwards into a collapsedconfiguration. The curved elongate portions 55 a and 55 c furtherinclude suture holes 53 and/or striations or bumps 56 along the outerperimeter to provide suture attachment points for the leaflets. Thestruts herein can be, for example, cut from flat metal sheet or tubing.

FIG. 15 shows three struts 5 from FIG. 11 coupled to central portion 3.FIG. 15 shows the subassembly from FIG. 1, but the view in FIG. 15 isfrom the ventricular side looking towards the atrial side.

As shown in FIG. 15, struts 5 are attached to central portion 3 with thestruts extending distally. In some embodiments there can be three struts5 located approximately 120 degrees away from one another around thecircumference of the central portion. In other embodiments, the threestrut legs may be located 90 degrees apart from each other with 30degree gaps between the legs of adjacent three strut legs.

Referring to FIGS. 16 and 2, in some embodiments, the valve prosthesis 1can include valve leaflets 20 a, 20 b, and 20 c attached, such as sewn,to struts 5. There can be three integral valve leaflets 20 a, 20 b, and20 c, and the leaflets can form a pressure actuated valve that providesuni-directional flow occlusion when the prosthesis 1 is implanted in avalve orifice. The leaflets 20 a-c can be constructed of bio-materials,such as bovine or porcine pericardium, or polymer materials.

FIG. 17 illustrates central portion 4 comprising optional skirt 120thereon or therearound formed of a biomaterial or thin polymer material.FIG. 17 is a perspective view of an exemplary prosthesis 1 with leaflets20 a-c, and skirt 120. The skirt can advantageously help seal prosthesis1 against the cardiac tissue when implanted. In some embodiments, theventricular anchor can include a skirt in place of, or in addition to,the skirt 120 on central portion 3. Additionally, a skirt can optionallybe on the atrial anchor portion as well.

FIG. 18 illustrates an exemplary strut 70. As shown in the embodiment ofstrut 70 in FIG. 18, a pin and slot mechanism (i.e., having an axiallyextending slot 83 along the middle elongate component 75 b), could beused to make up for the differences in the lengths of elongate portions75 a-c during collapse.

Some central portions herein or other portions of other replacementheart valves may be susceptible to undesirable deforming when implanted,such as due to movement during the heartbeat and/or in response topressures in the heart. In some embodiments the expandable anchorincludes an annular strut frame coupled to a radially inner portion ofthe central portion (i.e., within the central portion). An annular strutframe may distribute forces more evenly over the central portion of theexpandable anchor and may reduce the likelihood of undesirable centralportion deformation once implanted.

An annular strut frame, if used, is an additional layer of materialsecured to the radially inner portion of the central portion, whichreinforces and stabilizes the central portion when implanted.Additionally, by creating a coupling between the struts and the centralportion (as opposed to having a solid portion of material that canprovide additional stability), the flexibility of the coupling allowsfor relative movement of the struts during collapse of the device. Thiscan reduce stresses on the device as it is collapsed, allowing for asmaller delivery profile, which as discussed herein can be important fordelivery, such as a transseptal approach. The term annular in thiscontext does not require a perfect annulus.

When the prosthesis includes a strut frame, the struts can either beintegral to the strut frame or they can be separate components that aresecured to the strut frame during manufacturing.

FIG. 19 is a perspective view illustrating an exemplary annular strutframe 1000. Strut frame 1000 includes frame portion 1002 and pluralityof struts 1004. Struts 1004 extend further distally (i.e., in theventricular direction) than frame portion 1002, and are configured to besecured to replacement leaflets as described herein. The strut frame1000 has a ventricular end 1006 and an atrial end 1008. Strut portion1002 includes a plurality of arches, which define peaks 1012 and valleys1014. In this embodiment there are six strut frame arches, with twobetween adjacent struts 1004. Struts 1004 have an arch configurationdefined by first leg 1020 and second leg 1022, each of which has aplurality of suture apertures 1018 therein. Struts 1004 each also havefirst and second extensions 1024 and 1026 extending away from legs 1020and 1022 and towards atrial end 1008. Extensions 1024 and 1026 may alsobe considered part of the frame portion rather than the struts.Replacement leaflets are secured to struts 1004 at holes 1018 (e.g., bysuturing). The strut frame also includes a plurality of apertures 1010near the atrial end 1008, which are used to secure the annular strutframe to the central portion of the expandable anchor. The apertures arelocated at valleys 1014 in the frame portion. In some embodiments theannular strut frame is positioned radially within the central portion sothat each of apertures 1010 is aligned with an aperture in the centralportion, such as apertures 36. A coupler (e.g., rivet) is then advancedthrough the aligned apertures and one side of the coupler is thenplastically deformed to secure the annular strut frame to the centralportion.

FIG. 20 illustrates an exemplary annular strut frame 1100. Strut frame1100 includes three struts 1104 and frame portion 1102, which in thisembodiment includes one arch between adjacent struts 1104. Unlike theembodiment in FIG. 19, in which there is one coupling aperture 1010within each strut, in this embodiment there are two apertures 1110within each strut 1104. Just as in the embodiment in FIG. 19, there arealso apertures at the ends of each leg of struts. Strut frame 1100 iscoupled to a central portion by aligning apertures 1110 with aperturesin the central portion, such as aperture 36, and then extending acoupler through each set of aligned apertures, and plastically deformingeach coupler to secure the central portion to the annular strut frame atthe locations of the couplings.

FIGS. 19 and 20 illustrate exemplary strut frames in their expandedconfigurations, when the rest of the expandable anchor (e.g.,ventricular anchor, central portion, and atrial anchor) is also in anexpanded configuration. Strut frames 19 and 20 can be secured to, andconsidered part of, any of the expandable anchors herein.

In an exemplary method of manufacturing, the strut frame is cut from atubular element, then expanded, and set in the expanded configurationusing shape setting techniques described herein or otherwise known. Forexample, in an exemplary embodiment, the frame is cut from a 10 mmdiameter tube, then expanded to an expanded configuration of about 32 mm(as shown in FIG. 19), and set in the expanded configuration. In someexemplary embodiments the strut frames herein are 0.25 mm to about 0.45mm thick, such as about 0.35 mm thick.

The annular strut frame can be cut from a flat sheet and rolled up andsecured together (examples of which are described above), or it can becut from a tubular structure.

FIGS. 19 and 20 illustrate exemplary annular, or cylindrical, strutframes that are disposed radially within the central portion of theexpandable anchor. The central portion and the strut frame can bethought of as creating a composite cylinder when they are coupledtogether. The composite cylinder is thicker than each of the centralportion and strut frame individually. Each of the central portion andstrut frame is, however, relatively thin and can flex with respect tothe other component. The relative flexibility can make it easier tocollapse into a delivery configuration. If the composite region were asingle material with a thickness equivalent to the combined thickness ofthe central portion and strut frame, that modified region may not beable to collapse sufficiently to meet, for example, size constraintswithout overstraining. The central portion and strut frame acting as acomposite structure will not overstrain when collapsed into a collapsedconfiguration since the central portion and strut frame can flexindependently. The composite central portion and strut frame also, whenthe expandable anchor expands, has a thickness greater than eachcomponent individually, thus providing an increased thickness that maybe needed to resist torquing and other forces on the central portionwhen implanted. The composite central portion and cylindrical strutframe thus enables collapsing as needed without overstraining, as wellas provides a thickness to the central region that resists torquing anddeformation due to forces acting on the expandable anchor whenimplanted.

In some embodiments various components of the prosthesis are describedas being formed out of a flat sheet of material, but in some embodimentsthey can be formed out of a tubular element or other shape of material.

In some embodiments the configuration of the arches on the ventricularanchor portion might be the same as configuration shown herein (such asin FIG. 2), but the ventricular anchor portion could be a separate framethat is secured to the central portion, just as some atrial anchors aresecured to the central portion in exemplary embodiments herein. Bothanchors can be separate components secured to central portion (notintegral with central portion), and in some embodiments both ventricularand atrial anchors can be integral with the central portion.

In some embodiments, a prosthesis can include ventricular and atrialanchor portions that are both configured like anchor portion 2 herein.For example, both the ventricular and atrial anchor portions could beframes that are secured to the central portion. In some embodiments, aprosthesis can include ventricular and atrial anchor portions that areboth configured like anchor portion 4 herein.

The prostheses herein can be configured to self-expand within a cardiacvalve orifice such that the central portion lines the valve orificewhile the atrial and ventricular anchors sit within the chambers of theheart and pinch tissue of the orifice therebetween, securing theprosthesis in place. Methods of delivery and deployment of prosthesesthat are fully incorporated herein and can be used to deliver and deployany of the prostheses herein can be found in, for example, U.S. Pat. No.8,870,948, issued Oct. 28, 2014.

It is conceivable that the prostheses described herein can be used toreplace valves other than the mitral valve, such as the aortic valve,the tricuspid valve, and the pulmonary valve.

FIG. 21 illustrates an exemplary configuration of a portion ofexpandable anchor 1 (struts and leaflets not shown for clarity) in acollapsed configuration, in which only one atrial anchor frame has beensecured to central portion 3. The expandable anchor 1 can be configuredto be collapsed for delivery through a catheter. In the collapsedconfiguration (shown in FIG. 21), the atrial and ventricular anchors 2and 4, respectively, are extended outwards, and the entire expandableanchor can be radially collapsed. All of the arches become narrower, asdo the cells in central portion 3. The expandable anchor 1 in itscollapsed state can maintain a strain of less than 6% at all locations.A device and method for collapse is described in U.S. patent applicationSer. No. 14/170,388, filed Jan. 31, 2014, and titled “SYSTEM AND METHODFOR CARDIAC VALVE REPAIR AND REPLACEMENT,” now U.S. Pat. No. 8,870,948,the entire contents of which are incorporated by reference herein.

One aspect of the disclosure is a replacement mitral valve, comprising:a self-expandable anchor comprising a ventricular anchor, a centralportion, and an atrial anchor, the atrial anchor portion not beingintegral with the central portion and secured to the central portion,the self-expandable anchor having a self-expanded configuration in whichthe ventricular anchor and the atrial anchor are flared radially outwardrelative to the central portion such that the self-expandable anchor isconfigured to secure the replacement mitral valve to a mitral valveannulus in the self-expanded configuration, wherein the atrial anchorincludes a frame having a plurality of arches and a plurality ofapertures therethrough, and wherein the central portion includes aplurality of apertures therethrough, at least some of which are inalignment with one of the plurality of frame apertures; securing theframe to the central portion by extending a coupler through a centralportion aperture and a frame aperture, and plastically deforming thecoupler on one side of the aligned apertures, wherein plasticallydeforming the coupler secures the central portion and the frame at thelocation of the coupler; and a plurality of replacement leaflets securedto the expandable anchor.

Any of the individual components of any prostheses herein can beinterchanged with components in any other example, and the examplesdescribed herein are not limited to the specific components in thoseexamples.

What is claimed is:
 1. A replacement mitral valve, comprising: aself-expandable anchor comprising a ventricular anchor, a centralportion comprising a plurality of apertures therethrough that aredisposed around the central portion, and an atrial anchor, theself-expandable anchor having a self-expanded configuration in which theventricular anchor and the atrial anchor are flared radially outwardrelative to the central portion such that the replacement mitral valveis configured to be secured within a mitral valve orifice; an annularstrut frame comprising a plurality of apertures therethrough around thestrut frame, the strut frame disposed radially within the centralportion, each of the plurality of annular strut frame apertures alignedwith one of the plurality of central portion apertures to form aplurality of pairs of apertures; a plurality of couplers, each couplerextending through one of the pairs of aligned apertures to fasten theannular strut frame to the central portion; and a plurality ofreplacement leaflets secured to the annular strut frame.
 2. Thereplacement mitral valve of claim 1 wherein the strut frame comprises aplurality of struts extending distally from a frame portion of the strutframe and distally from the central portion.
 3. The replacement mitralvalve of claim 2 wherein the strut frame comprises a plurality of strutarches, wherein at least one strut arch is disposed between each of theadjacent struts.
 4. The replacement mitral valve of claim 1, wherein atleast some of the plurality of couplers are configured to allow formovement in at least one direction between the central portion and theannular strut frame at locations of the pairs of aligned apertures. 5.The replacement mitral valve of claim 1, wherein the plurality ofcouplers comprises a plurality of rivets.
 6. The replacement mitralvalve of claim 2, wherein the plurality of struts are integral with theframe portion.
 7. The replacement mitral valve of claim 2, wherein eachof the plurality of struts forms a substantially triangular shape. 8.The replacement mitral valve of claim 2, wherein each of the pluralityof struts includes a plurality of diamond-shaped cells therein.
 9. Thereplacement mitral valve of claim 1, wherein the central portion and theannular strut frame are configured to flex relative to one another. 10.The replacement mitral valve of claim 1, wherein the annular strut frameis configured to reduce torquing and deformation of the replacementvalve.
 11. The replacement mitral valve of claim 1, wherein the annularstrut frame is configured to self-expand from a constrainedconfiguration to an expanded configuration.
 12. The replacement mitralvalve of claim 11, wherein the replacement valve is configured toforeshorten upon expansion of the anchor assembly from the constrainedconfiguration to the expanded configuration.